Answer:

Step-by-step explanation:

Answer:
-9a + b + 36
Step-by-step explanation:
Answer: D
Explanation: For this problem you can substitute f(x) and x for 21 and -6 respectively.
Thus, we have 21=-3(-6)+4
Answer:
B if there is an N at the end or beginning of it, Not sure if it cut off or not.
Step-by-step explanation:
Well you would need to do 20(7) to get 140, then multiply that to N. I would say B because I'm assuming you're missing out on some part of it, if it is N at the beginning or end then it is B.